• Detects the most common wiring problems in standard and GFCI receptacles • Works on GFI outlets and confirms operation of the ground fault protective device • Built to withstand a 6.6' (2m) drop • Operating temp: 32-degrees F to 140-degrees F (0-degrees C to 40-degrees C) • Nominal Voltage: 110/125V AC at 50/60Hz in 3-wire outlet • Conforms to UL Std 1436, Certified to CSA Std C22.2 #160